<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<link rel="stylesheet" type="text/css" href="01.css">
	
</head>
<body>
	我是某某某

	<div>
		2222222
	</div>


	<p>333333333</p>

	<h3>我是谁</h3>
	<ul id="mune">
		<li><p><a href="#">哈哈<span>我是span标签</span></a></p></li>
		<li><p><a href="#">嘿嘿</a></p></li>
	</ul>
	<div id="box">
		<p>我是子代选择器</p>
	</div>
	<div id="four">
		<span>我是后代选择器</span>
	</div>
</body>
</html>